Soluble gilsonite and method of making same



Patented May 5, .1931

UNITED STATES PATENT OFFICE;

IZADOR J. NOVAK, BRIDGEPORT, OONNECTICUI ASSIGNOR TO THE IILVAYBESTOS COM PANY, OF BRIIJGEPORT, CONNECTICUT, A CORPORATION 'OF CONNECTICUT SOLUBLE GILSONITE AND METHOD OF MAKING SAME No Drawing.

smooth, substantially sediment-free solution 7 of the same.

It is well known that commercial gilsonite is very difficult to completely dissolve in the ordinary solvents such as gasoline or ben- 201 unless, for instance, it is refluxed with these solvents at a high temperature. This is probably due to the fact that gilsonite is highly colloidal and, therefore, tends to resist.

complete smooth solution.

With ordinary straight run gasoline and a gilsonite havin a melting point of approximately 300 (ball and ring method) and ash of 0.2%, the maximum amount of gilsonite which enters the solvent, evenwhen finely ground, is about 70 to 7 5%. It is slightly higher with benzol80 to- 90%. In both cases, however, there isa considerable proportion which never goes into solution and further, most of the material in solution is still colloidal and swelled rather than dis solved and, therefore, is poorly suited as a saturating material for brake linings for instance, where a considerable proportion of.

colloidal material is left on the surface when impregnation is attempted- I I have found that, by melting gilsonite such as described above and holding it slightly above the temperature at which it is comratively fluid, which may be, say,-325400 for a period of one-half hour, more or less, the gilsonite is rendered exteremely soluble in both gasoline and benzol without material lowering of the original melting point. As i a matter of fact, in most cases, no lowering is observed. After cooling, I 'find that such a previously melted gilsonite goes easily and quickly into solution in gasoline and benzol or other similar or related solvents, leaving no appreciable residue except the inorganic matter which was contained.

After months of standing, such solutions in gasoline have shown no appreciable sedi- Application filed July 26,

1929. Serial No. 381,405.

ment and are smooth and homogeneous.

Further, it quickly and thoroughly saturates, for instance, woven asbestos-covered wire tape without leaving sediment on the surface indicating that the colloidal characteristics of the untreated much reduced.

By the term gilsonite I wish to indicate gilsonite have been Very asphaltites having a fusing point over 250 F. and a specific gravity between 1.05. and 1.12, fixed carbon 10-25%, solubility in carbon bisulfide greater than 96%. This is intended to include certain of the glance pitches which are so close in physical properties to true gilsonite that they are or may be used for the same purpose.

I am aware that it is customary to make certain varnishes by. combining gilsonite with natural gums and drying oils at high temperatures whereby the gilsonite becomes truly soluble, but the intent of this invention is to produce a truly soluble gilsonite per se and not a combination with oils.

I claim as my invention:

1. A method for rendering gilsonite substantially completely soluble in gasoline and ature slightly above its melting point for a time period sufficient to induce substantially complete solubility when mixed with the sol vent.

2. 'A method for rendering gilsonite substantially completely soluble in gasoline and like solvents and for reducing the colloidal characteristics thereof which comprises melting the gilsonite by heating in the absence of the solvent and holding the same at a temperature of 325 F. to 400 F. for at least onehalf hour.

3. A process for producing a substantially complete solution of gilsonite in gasoline which comprises melting the gilsonite by heating in the absence of the gasoline and holding the same at a temperature slightly above its melting point for a time period suflicient to induce substantially complete solubility in gasoline, and subsequently dissolv- 5 ing the thus treated gilsonite in gasoline.

4. A process for producing a substantially complete solution of gilsonite in gasoline which comprises melting the gilsonite by heating in the absence of the gasoline and holding the same at a temperature of 325 F. to 400 F. for at least one-half hour, and subsequently dissolving the thus treated gilsonite in gasoline.

In testimony WhereofI affix my signature.

IZADOR J. NOVAK. 

